Carbon dioxide conversion to hydrocarbon fuel via syngas production cell harnessed from solar radiation

ABSTRACT

A process for converting carbon dioxide to hydrocarbon fuels using solar energy harnessed with a solar thermal power system to create thermal energy and electricity, using the thermal energy to heat a fuel feed stream, the heated fuel feed stream comprising carbon dioxide and water, the carbon dioxide captured from a flue gas stream, converting the carbon dioxide and water in a syngas production cell, the syngas production cell comprising a solid oxide electrolyte, to create carbon monoxide and hydrogen, and converting the carbon monoxide and hydrogen to hydrocarbon fuels in a catalytic reactor. In at least one embodiment, the syngas production cell is a solid oxide fuel cell. In at least one embodiment, the syngas production cell is a solid oxide electrolyzer cell.

RELATED APPLICATIONS

This patent application is a continuing application of U.S. patentapplication Ser. No. 14/147,067, filed on Jan. 3, 2014. For purposes ofUnited States patent practice, this application incorporates thecontents of the prior application by reference in its entirety.

FIELD OF THE INVENTION

This invention relates to a process and system for the capture of wastegas and the conversion of the waste gas to hydrocarbon fuel. Morespecifically, this invention relates to a process and system forcapturing carbon dioxide (CO₂) and water vapor (H₂O) and subsequentlyconverting the CO₂ and H₂O to hydrocarbon fuel harnessing solar energy.

BACKGROUND OF THE INVENTION

The use of fossil fuels for power generation grows increasinglyproblematic. First, petroleum consumption has increased even asworld-wide petroleum reserves have declined. For example, Saudi Arabia'sdomestic petroleum consumption due to power generation is expected to be8 million barrels/day by 2028, which means a reduction of the quantitiesavailable for export. Second, concerns about air quality may result instringent regulations such as a carbon tax aimed at reducing carbonemissions.

Given Saudi Arabia's abundant quantities of solar radiation energy,solar power capture coupled with solar storage represents an opportunityto address both issues. Conventional solar storage and capture systemsinclude photovoltaics and solar thermal systems.

Photovoltaics convert solar energy into electrical current due to thephotovoltaic effect of certain substances, such as silicon or organicsolar materials. Photovoltaics are capital intensive, but excellent forsmall scale electricity generation, for example, homes, outdoor lights,highway signs. For larger systems, such as those that contribute to theelectricity grid, solar thermal systems, or concentrating solar power(CSP) systems, are preferred. Existing CSP systems include, for example,the linear Fresnel reflector system, the trough system, the dish system,and the tower system.

CSP systems convert solar radiation energy into thermal energy usingheliostats. Heliostats are mirrors, typically flat, which are mountedsuch that they move on an axis to track the movement of the sun duringdaylight hours. Heliostats concentrate the solar radiation (sunlight)onto a receiver, which uses the thermal energy from the solar radiationto heat a working fluid. The working fluid, a heat transfer fluid, suchas water (H₂O) or molten salt, exits the heliostat/receiver system whereit exchanges heat with H₂O to generate steam. When H₂O is the workingfluid, the steam is generated directly from the heated working fluid.The steam runs a steam turbine, which drives a generator to produceelectricity.

All CSPs operate under the same basic principles, the differences lie inthe shape and layout of the heliostats and the spatial relationship ofthe heliostats to the receiver. For example, in a linear Fresnelreflector system, the heliostats are long flat tracks of mirrors. Thereceiver is a tube fixed in space above the mirrors. A trough systemuses parabolic mirrors and a tube positioned along the focal line of thereflectors, requiring a large number of reflectors. Dish system CSPsalso use parabolic shaped reflectors; a large parabolic dish covered inmirrors directs sunlight to a receiver mounted on the dish along thefocal line of the mirrors. A dish system CSP produces relatively littleelectricity compared to other CSP systems. Tower system CSPs employlarge numbers of heliostats typically arrayed in lines. The receiversits on the top of a tall tower and the heliostats focus the solarenergy onto the receiver. A tower CSP is capable of producing up to 200megawatts of electricity.

In addition to the ability to generate large amounts of electricity,another advantage of solar thermal systems over photovoltaics is theability to store thermal energy in the working fluid. The working fluidsmay be stored in tanks until the thermal energy is needed forelectricity generation. Thus, allowing generation even when there is nodirect sunlight, such as at night or in stormy weather. Even still, thestorage of a working fluid is not a long term solution, due to the sizeof the tanks needed for storage and eventual heat loss. Thus, theconversion of solar thermal energy to fuel is an attractive alternative.

The emission of CO₂ into the atmosphere is increasingly under attack.Carbon capture technologies are being explored as a way to remove andstore the CO₂ from waste gas. Carbon capture technologies are broadlycategorized as to whether the capture technology is post-combustion,pre-combustion, or oxyfuel combustion. Post-combustion technologiestypically include solvent capture systems, which use a solvent to absorbCO₂ from a waste gas stream and then use heat to remove the absorbed CO₂from the solvent stream. The resulting stream is a nearly pure stream ofCO₂. Post-combustion technologies are commonly used with fossil fuelburning power plants. Other post-combustions technologies include, forexample, calcium looping cycle or chemical looping combustion.

Current storage (or sequestration) schemes most commonly includegeological sequestration, in which the carbon is stored in undergroundformations. Depleted oilfields, unmineable coal deposits, and salineformations provide naturally occurring formations appropriate for thestorage of CO₂. These formations, however, suffer from set-backsincluding, for example, their locations, the costs to inject the CO₂into the ground, and the concerns about leakage out of the formation atsome later point.

An alternative to sequestration of CO₂ is to convert the CO₂ to otheruseful components. One way to achieve conversion is using a fuel cell toconvert the CO₂ with the added benefit of generating electricity. Fuelcells contain three sections: an anode, a cathode, and an electrolyte.Redox reactions occur at the anode and the cathode. In many cases, theoverall effect is to convert H₂O to hydrogen (H₂) and oxygen (O₂).

Fuel cells are categorized by their electrolyte. One category of fuelcells uses a solid oxide electrolyte. Solid oxide fuel cells reduceoxygen on the cathode side, a current is applied to the cathode so thatit is negatively charged and conductive. The oxygen ions diffuse throughthe cathode, the solid oxide electrolyte, and the anode so thatoxidation reactions occur on the anode side. The oxidation reactionsgenerate electrons which can be carried through the anode to generate anelectricity supply. The anode, cathode, and solid oxide electrolyte ofsolid oxide fuel cells are composed of ceramic materials and operated attemperatures above 500° C. to ensure the proper functioning of theceramic materials. The ceramic materials can be porous. Porosity is notrequired for the passage of oxygen ions from the electrode to theelectrolyte. The porosity of the anode impacts theelectrolyte/electrode/gas interface area (three phase boundaries), andthus impacts oxygen ion formation rate. The porosity also enhances thediffusivity of molecular oxygen from the gas phase to the three phaseboundaries. Solid oxide fuel cells have been shown to have highefficiencies.

A solid oxide fuel cell run in a “regenerative” mode is often called asolid oxide electrolysis cells. Solid oxide electrolysis cellselectrolyze components by a reduction process on the cathode side, thuscapturing oxygen ions, which diffuse through the cathode, the solidoxide electrolyte, and the anode to form oxygen molecules on the anodeside of the cell. The electrolysis of H₂O is endothermic, thus the highoperating temperatures of a solid oxide electrolysis cell make theelectrolysis reaction thermodynamically favored. In addition, the hightemperature increases the kinetics of the reaction. High temperatureelectrolysis has the advantage of high conversion efficiency, above 90%conversion of CO₂ is expected according to some estimates.

SUMMARY OF THE INVENTION

The present invention relates to a process and system for the capture ofwaste gas and the conversion of the waste gas to hydrocarbon fuel. Morespecifically, this invention relates to a process and system forcapturing carbon dioxide (CO₂) and water vapor (H₂O) and subsequentlyconverting the CO₂ and H₂O to hydrocarbon fuel harnessing solar energy.

In one aspect of the present invention, a process for converting carbondioxide to hydrocarbon fuels using solar energy is provided. The processincludes the steps of receiving direct sunlight with a plurality ofheliostats and reflecting the direct sunlight from the heliostats asreflected sunlight onto a tower receiver, where the reflected sunlightheats a heat transfer fluid in the tower receiver, converting a waterstream to a generated steam stream in a steam generator, where the heattransfer fluid provides heat to the steam generator. The generated steamstream is fed to a steam turbine, the steam turbine converts thermalenergy in the generated steam stream to mechanical energy to drive anelectric generator to generate electricity. The process further includesthe steps of heating a fuel feed stream by transferring thermal energyfrom the heat transfer fluid to create a heated fuel feed stream, suchthat the heated fuel feed stream reaches a temperature of between 650°C. and 800° C., feeding the heated fuel feed stream to a syngasproduction cell, where the heated fuel feed stream includes carbondioxide and water, wherein the carbon dioxide is captured from a fluegas stream, converting the carbon dioxide and water in the heated fuelfeed stream to carbon monoxide and hydrogen in the syngas productioncell to produce a syngas stream, wherein the syngas production cellincludes a solid oxide electrolyte, feeding the syngas stream to acatalytic reactor, wherein the catalytic reactor operates in thepresence of a catalyst, and converting the syngas stream to ahydrocarbon fuel stream in the catalytic reactor.

In certain embodiments of the present invention, the syngas productioncell includes a solid oxide electrolyzer cell, where the solid oxideelectrolyzer cell includes a porous cathode, the solid oxideelectrolyte, and a porous anode. In certain embodiments of the presentinvention, the step of converting the carbon dioxide and water in theheated fuel feed stream to carbon monoxide and hydrogen in the syngasproduction cell further includes the steps of supplying the electricityto the porous cathode of the solid oxide electrolyzer cell, contactingthe porous cathode with fuel feed stream, reducing the carbon dioxide tocreate carbon monoxide and oxygen ions, wherein the oxygen ions passthrough the porous cathode to the solid oxide electrolyte, reducing thewater to create hydrogen and oxygen ions, wherein the oxygen ions passthrough the porous cathode to the solid oxide electrolyte, diffusing theoxygen ions through the solid oxide electrolyte to the porous anode, andreleasing electrons from the oxygen ions at the porous anode, such thatoxygen molecules are formed to create an oxygen stream. In certainembodiments of the present invention, the syngas production cellincludes a solid oxide fuel cell, wherein the solid oxide fuel cellincludes a porous anode, the solid oxide electrolyte, and a porouscathode. In certain embodiments of the present invention, the step ofconverting the carbon dioxide and water in the heated fuel feed streamto carbon monoxide and hydrogen in the syngas production cell furtherincludes the steps of adding a gaseous hydrocarbon to the heated fuelfeed stream, feeding the heated fuel feed stream to the porous anode ofthe solid oxide fuel cell, reforming the water and the gaseoushydrocarbon in the heated fuel feed stream to create carbon monoxide andhydrogen, reforming the carbon dioxide and the gaseous hydrocarbon inthe heated fuel feed stream to create carbon monoxide and hydrogen,reducing oxygen from an oxygen supply on the porous cathode of the solidoxide fuel cell to generate oxygen ions, diffusing the oxygen ionsthrough the solid oxide electrolyte to the porous anode, oxidizing thehydrogen at the porous anode with the oxygen ions to create water andelectrons, oxidizing the methane at the porous anode with the oxygenions to create carbon monoxide, hydrogen, and electrons, and supplyingthe electrons to an electrical substation, wherein the electricalsubstation is configured to combine the electrons from the syngasproduction cell with the electricity generated by the electricgenerator. In certain embodiments of the present invention, the gaseoushydrocarbon includes methane. In certain embodiments of the presentinvention, the process further includes the step of feeding thehydrocarbon fuel to a power plant for consumption.

In a second aspect of the present invention, a system to convert carbondioxide to hydrocarbon fuels using solar energy is provided. The systemincludes a solar thermal power system configured to convert solar energyto thermal energy and electricity, the solar thermal power system beingin thermal communication with a syngas production cell, wherein thesyngas production cell is configured to receive thermal energy from thesolar thermal power system, the syngas production cell including a fuelside including a fuel inlet configured to receive a fuel feed stream anda fuel outlet configured to receive a syngas stream, and an oxygen sideincluding an oxygen outlet configured to receive an oxygen stream,wherein the fuel feed stream includes carbon dioxide and water, whereinthe syngas production cell is configured to convert the carbon dioxideand water into carbon monoxide and hydrogen, the carbon monoxide andhydrogen operable to form the syngas stream, and a catalytic reactorfluidly connected to the fuel side of the syngas production cell, thecatalytic reactor being configured to convert the syngas stream from thefuel side of the syngas production cell to a hydrocarbon fuel stream,the catalytic reactor including a reactor bed, the reactor bed includinga catalyst and a distributor, wherein the catalytic reactor isconfigured to operate from 250° C. to 650° C.

In certain embodiments of the present invention, the syngas productioncell includes a solid oxide electrolyzer cell. In certain embodiments ofthe present invention, the solid oxide electrolyzer cell includes aporous cathode in fluid communication with the fuel side of the syngasproduction cell, the porous cathode having a fuel side of the porouscathode configured to transfer electrons to the fuel feed stream, suchthat carbon monoxide, hydrogen, and oxygen ions are produced, and anelectrolyte side configured to release the oxygen ions into a solidoxide electrolyte, where the porous cathode is configured to allowpassage of oxygen ions, a porous anode in fluid communication with theoxygen side of the syngas production cell, the porous anode including anelectrolyte side configured to receive oxygen ions from the solid oxideelectrolyte, and an outlet side configured to convert oxygen ions tooxygen molecules to form an oxygen stream, where the porous anode isconfigured to allow passage of oxygen ions, the solid oxide electrolyte,the solid oxide electrolyte lies between the porous cathode and theporous anode, wherein the solid oxide electrolyte is configured to allowpassage of oxygen ions, and an electron supply, wherein the electricityfrom the solar thermal power system provides the electron supply to theporous cathode and accepts electrons from the porous anode. In certainembodiments of the present invention, the porous anode and the porouscathode are selected from the group containing nickel/yttria-stabilizedzirconia (Ni-YSZ), Lanthanum Strontium Manganese Oxide-YSZ (LSM-YSZ),and a ceramic oxide of perovskite. In certain embodiments of the presentinvention, the solid oxide electrolyte contains yttria stabilizedzirconia. In certain embodiments of the present invention, the syngasproduction cell includes a solid oxide fuel cell and the fuel feedstream further includes a gaseous hydrocarbon. In certain embodiments ofthe present invention, the gaseous hydrocarbon includes methane. Incertain embodiments of the present invention, the solid oxide fuel cellincludes a porous anode in fluid communication with the fuel side of thesyngas production cell, the porous anode comprising a fuel side of theporous anode configured to accept electrons, such that the methaneundergoes an oxidation reaction to form carbon monoxide, hydrogen, andelectrons, and an electrolyte side configured to accept oxygen ions froma solid oxide electrolyte, where the porous anode is configured to allowpassage of oxygen ions, where the methane and water react in thepresence of the fuel side of the porous anode to generate carbonmonoxide and hydrogen, and where the methane and carbon dioxide react inthe presence of the fuel side of the porous anode to generate carbonmonoxide and hydrogen, a porous cathode in fluid communication with theoxygen side of the syngas production cell, the porous cathode comprisingan outlet side configured to convert oxygen into oxygen ions and anelectrolyte side configured to release oxygen ions into the solid oxideelectrolyte, where the porous cathode is configured to allow passage ofoxygen ions, and the solid oxide electrolyte, the solid oxideelectrolyte lies between the porous cathode and the porous anode,wherein the solid oxide electrolyte is configured to allow passage ofoxygen ions. In certain embodiments of the present invention, thehydrogen in the fuel side of the syngas production cell undergoes anoxidation reaction to form water and electrons. In certain embodimentsof the present invention, the porous cathode and the porous anode areselected from the group containing nickel/yttria-stabilized zirconia(Ni-YSZ), Lanthanum Strontium Manganese Oxide-YSZ (LSM-YSZ), and aceramic oxide of perovskite. In certain embodiments of the presentinvention, the solid oxide electrolyte contains yttria stabilizedzirconia. In certain embodiments of the present invention, the solarthermal power system includes a tower concentrating solar power system,the tower concentrating solar power system including a tower receiverconfigured to heat a heat transfer fluid, a plurality of heliostats inproximity to the tower receiver, wherein the heliostats are configuredto receive direct sunlight and reflect the direct sunlight from theheliostats as reflected sunlight onto the tower receiver, a hot storagetank fluidly connected to the tower receiver, the hot storage tankconfigured to store the heat transfer fluid, a steam generator fluidlyconnected to the hot storage tank, the steam generator configured totransfer heat from the heat transfer fluid to a water stream to create agenerated steam stream, a steam turbine fluidly connected to the steamgenerator, wherein the generated steam stream is configured to drive thesteam turbine, and an electric generator mechanically connected to thesteam turbine, where the steam generator is configured to drive theelectric generator to create electricity. In certain embodiments of thepresent invention, the syngas production cell operates from 650° C. to800° C. In certain embodiments of the present invention, the system toconvert carbon dioxide to hydrocarbon fuels further includes a carboncapture system configured to remove carbon dioxide from a flue gasstream to create a carbon dioxide stream, the carbon capture system influid communication with a power plant, wherein the power plant isconfigured to produce a flue gas stream.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the presentinvention will become better understood with regard to the followingdescriptions, claims, and accompanying drawings. It is to be noted,however, that the drawings illustrate only several embodiments of theinvention and are therefore not to be considered limiting of theinvention's scope as it can admit to other equally effectiveembodiments.

FIG. 1 is a process flow diagram of an embodiment of the presentinvention.

FIG. 2 is a schematic of an embodiment of the solar thermal powersystem.

FIG. 3 is a plan view of an embodiment of the syngas production cell.

FIG. 4 is a plan view of an embodiment of the syngas production cell.

FIG. 5 is a schematic of an embodiment of the carbon capture system.

DETAILED DESCRIPTION OF THE INVENTION

While the invention will be described with several embodiments, it isunderstood that one of ordinary skill in the relevant art willappreciate that many examples, variations and alterations to theapparatus and methods described herein are within the scope and spiritof the invention. Accordingly, the exemplary embodiments of theinvention described herein are set forth without any loss of generality,and without imposing limitations, on the claimed invention.

FIG. 1 provides a process flow diagram of an embodiment of the presentinvention. Solar thermal power system 100 converts direct sunlight 2into thermal energy 10. Direct sunlight 2 consists of solar energyacross all wavelengths. Solar thermal power system 100 can be any typeof solar thermal power system that can convert solar energy to thermalenergy and electricity.

Carbon capture system 400 separates CO₂ from flue gas 50 of operatingunit 500 and generates waste gas 40. Waste gas stream 40 is disposed ofas required by the composition of the stream. In at least one embodimentof the present invention, waste gas stream 40 is vented to atmosphere.

The CO₂ from carbon capture system 400 is mixed with other streams (notshown) to create fuel feed stream 4. Fuel feed stream 4 contains CO₂. Inat least one embodiment of the present invention, fuel feed stream 4contains H₂O, in addition to CO₂. In at least one embodiment of thepresent invention, fuel feed stream contains CO₂, H₂O, and gaseoushydrocarbons. Exemplary gaseous hydrocarbons include methane (CH₄),ethane (C₂H₆), butane (C₃H₈), and combinations thereof. In at least oneembodiment of the present invention, fuel feed stream 4 contains CO₂,H₂O, and CH₄. In at least one embodiment of the present invention, fuelfeed stream 4 contains CO₂, H₂O, CH₄, and inert gases. In at least oneembodiment, fuel feed stream 4 is in the absence of nitrogen containingcompounds and sulfur containing compounds. The exact temperature,pressure, and composition of fuel feed stream 4 will depend on thestreams that are mixed together to create fuel feed stream 4.

Operating unit 500 can be any type of operating unit that produces anexhaust gas, a flue gas, or waste gas containing CO₂. Operating unit 500includes, for example, a power plant that burns fossil fuels or otherhydrocarbons and produces electricity, a steel mill which produces CO₂as a waste gas of the process, or any other type of production unit.Flue gas 50 includes, for example, any type of flue gas that contains anamount of CO₂. In accordance with at least one embodiment of the presentinvention, flue gas 50 includes an amount of CO₂ and an amount of H₂O.In accordance with at least one embodiment, operating unit 500 is apower plant. In at least one embodiment of the present invention, fluegas 50 is from a gas-fired power plant and has a composition of betweenabout 7.4% and about 7.7% CO₂, about 14.6% H₂O, about 4.45% O₂, andbetween about 73% and about 74% N₂, with the remainder includingnitrogen containing compounds, sulfur containing compounds, and variousother gases. Alternately, flue gas 50 from, for example, a coal-firedpower plant can have a composition of between about 12.5% and about12.8% CO₂, about 6.2% H₂O, about 4.4% O₂, and between about 76% andabout 77% N₂, with the remainder including nitrogen containingcompounds, sulfur containing compounds, and various other gases.

In accordance with one embodiment, flue gas 50 is subjected to scrubbingtechnologies (not shown) prior to feeding to carbon capture system 400.Any known scrubbing technologies capable of removing sulfur and nitrogencontaining compounds from flue gas 50 can be used. Scrubbingtechnologies can optionally remove particulate matters. Conventionalscrubbing technologies include wet scrubbers and electrostaticseparators.

Thermal energy 10 provides heat to syngas production cell 200, heatingsyngas production cell 200 to a temperature between about 500° C. andabout 1000° C., alternately between about 600° C. and about 900° C.,alternately between about 650° C. and about 800° C., and alternatelybetween about 700° C. and about 800° C. Heat from thermal energy 10 canbe transferred by a heat exchanger (not shown) to heat the feed streamsto syngas production cell 200. In at least one embodiment of the presentinvention, thermal energy 10 provides heat to fuel feed stream 4 tocreate the heated fuel feed stream (not shown) to syngas production cell200.

Syngas production cell 200 uses thermal energy 10 to convert fuel feedstream 4 to syngas stream 22. Syngas stream 22 contains synthesis gas,or syngas. Syngas is a gas stream containing a combination of CO and H₂.In at least one embodiment of the present invention, syngas stream 22also contains CO₂ and H₂O. The exact composition of syngas stream 22 isdetermined after consideration of the temperature, pressure, andconfiguration of syngas production cell 200.

Syngas stream 22 is fed to catalytic reactor 300. Catalytic reactor 300converts the syngas in syngas stream 22 to hydrocarbons to createhydrocarbon fuel stream 30. In at least one embodiment, hydrocarbon fuelstream 30 include alkanes, alcohols, acids, ethers, and combinationsthereof. The composition of hydrocarbon fuel stream 30 depends on thecatalyst used in catalytic reactor 300 and the composition of syngasstream 22. In at least one embodiment of the present invention, anycatalyst which converts CO and H₂ to hydrocarbons is used in catalyticreactor 300. Exemplary catalysts include a Fischer-Tropsch catalyst, amethanation catalyst, or combinations thereof. The catalyst can includetransition metals such as iron, cobalt, nickel, copper, zinc, ruthenium,rhodium, palladium, platinum, or combinations thereof. Catalytic reactor300 operates a temperature of between about 200° C. and about 700° C.,alternately between about 250° C. and about 650° C., and alternatelybetween about 300° C. and about 600° C. In accordance with at least oneembodiment of the present invention, at operating conditions of 300° C.and high pressures the catalyst is a blend of copper and zinc oxide. Inother embodiments of the present invention, at operating conditions of600° C. and low pressures, the catalyst includes iron. Catalysts caninclude a catalyst support, such as a zeolite. The distributor (notshown) supports the catalyst in catalytic reactor 300, the size andshape of the distributor is dependent on the type of catalytic reactor300 and the type of catalyst. Catalysts are chosen in consideration ofthe operating conditions in catalytic reactor 300 and the reactionproduct composition desired. According to various embodiments, catalyticreactor 300 includes a packed bed reactor or a fluidized bed reactor.

According to one embodiment of the present invention, the catalyst ischosen such that the catalytic conversion of syngas stream 22 tohydrocarbon fuel stream 30 occurs according to the following reaction:

(2n+1)H₂ +nCO->C_(n)H_((2n+2)) +nH₂O

In at least one embodiment of the present invention, conversion ofsyngas stream 22 creates CH₄ and H₂O (n=1).

In an alternate embodiment of the present invention, the catalyst ischosen such that the catalytic conversion of syngas stream 22 tohydrocarbon fuel stream 30 includes the following reactions:

2H₂+CO→CH₃OH

2CH₃OH→CH₃OCH₃+H₂O

CO+CH₃OH→CHO₂CH₃

CHO₂CH₃+H₂O→CHO₂H+CH₃OH

The reaction products of the above reactions include methanol (CH₃OH),dimethyl ether (DME) (CH₃OCH₃), and formic acid (CHO₂H).

Hydrocarbon fuel stream 30 is fed to operating unit 500. In certainembodiments, hydrocarbon fuel stream 30 can be stored (not shown) ortransported offsite (not shown). In at least one embodiment, hydrocarbonfuel stream 30 undergoes additional processing steps to separate thecomponents of hydrocarbon fuel stream 30. In at least one embodiment ofthe present invention, the additional processing steps separate H₂O fromhydrocarbon fuel stream 30.

Notably, the embodiment of the invention as shown and described in FIG.1 creates a hydrocarbon fuel useful for power generation, without theuse of a fossil fuel at any stage in the system.

FIG. 2 provides a schematic of an embodiment of solar thermal powersystem 100. According to this embodiment, direct sunlight 2 hitsheliostats 102 and reflected sunlight 12 is focused onto tower receiver104. Heliostats 102 are designed to reflect specific wavelengths ofdirect sunlight 2, such that direct sunlight 2 can be converted tothermal energy, electricity, or mechanical energy. Reflected sunlight 12is solar energy across the specific wavelengths reflected by heliostats102. Tower receiver 104 provides thermal energy 10 from the sunlight tosyngas production cell 200, as described in reference to FIG. 1.

According to various embodiments, tower receiver 104 focuses reflectedsunlight 12 to raise the temperature of heat transfer fluid 14. Heattransfer fluid 14 includes, for example, any heat transfer fluid,including water, salt water, or a molten salt, such as sodium nitratesalt, potassium nitrate salt, calcium nitrate salt, lithium nitratesalt, or combinations thereof. Other molten salts include, for example,lithium, sodium, potassium, rubidium, cesium, francium, beryllium,magnesium, calcium, strontium, barium, radium, fluorine, chlorine,bromine, and iodine. Molten salts have an advantage over water becausethey retain heat for longer periods of time. In at least one embodimentof the present invention, heat transfer fluid 14 includes a blend ofsodium chloride and potassium chloride. Heat transfer fluid 14 reaches atemperature between about 500° C. and about 1000° C., alternatelybetween about 600° C. and about 900° C., alternately between about 650°C. and about 800° C., and alternately between about 700° C. and about800° C.

According to various embodiments, heat transfer fluid 14 can be storedin hot storage tank 106 for later use (i.e., when there is no longerdirect sunlight 2) as stored transfer fluid 15. When needed, storedtransfer fluid 15 is fed from hot storage tank 106 to steam generator108. Steam generator 108 transfers heat from stored transfer fluid 15 towater stream 8 to create generated steam stream 16 and steam supply 6.Steam generator 108 can be any device capable of producing steam tooperate a turbine. Steam generator 108 includes, for example, a boileror a supercritical steam generator (Benson boiler). Water stream 8originates from any source of water capable of producing steam.According to various embodiments, steam supply 6 is fed to syngasproduction cell 200. Steam supply 6 provides both H₂O (as vapor) andheat to syngas production cell 200.

Steam generator 108 extracts heat from stored transfer fluid 15 andcreates used transfer fluid 11. According to at least one embodimentused transfer fluid 11 is stored in cold storage tank 114 as coldtransfer fluid 13. When needed, cold transfer fluid 13 is fed from coldstorage tank 114 to tower receiver 104, where it is heated and becomesheat transfer fluid 14.

As used herein, heat transfer fluid 14, stored transfer fluid 15, usedtransfer fluid 11, and cold transfer fluid 13 are the same fluid atdifferent stages in the solar thermal process.

According to various embodiments, generated steam stream 16 is fed tosteam turbine 110, steam turbine 110 converts the thermal energy ingenerated steam stream 16 to mechanical energy (i.e., a rotating shaft),the mechanical energy drives electric generator 112. Steam turbine 110includes, for example, any type of steam turbine including condensing,non-condensing, reheat, extraction, and induction. The rating/size ofthe turbine will depend on the quantity of electricity produced byelectric generator 112. Electric generator 112 generates electricity 18.Examples of electric generators useful in this invention include Seebeckgenerators and thermoelectric generators. Electricity 18 provideselectricity to syngas production cell 200. In at least one embodiment ofthe present invention, electricity 18 provides electricity to otherprocess units (not shown), to an electrical substation (not shown), orto the local electric grid (not shown). In at least one embodiment ofthe present invention, solar thermal power system 100 is capable ofgenerating up to about 200 MW of electricity.

FIG. 3 provides a plan view of an embodiment of syngas production cell200, wherein syngas production cell 200 includes solid oxideelectrolyzer cell (SOEC) 220. SOEC 220 includes porous cathode 202,solid oxide electrolyte 204, and porous anode 206. Electricity 18provides electrons to porous cathode 202, thus porous cathode 202 isnegatively charged. Porous cathode 202 can be any material that allowsfor the transfer of electrons and/or negatively charged ions through thematerial. In at least one embodiment of the present invention, porouscathode 202 is any material that allows the electrons to pass through toreact with components in fuel side 210. In at least one embodiment, thematerial of porous cathode 202 allows the transfer of electrons fromporous cathode 206 to CO₂ and H₂O in fuel side 210 and allows oxygenions to diffuse through from fuel side 210 to the electrolyte side (notshown). Porous cathode 202 can be a cermet, a composite material ofceramic and a metal. Cermets include, for example,nickel/yttria-stabilized zirconia (Ni-YSZ) or Lanthanum StrontiumManganese Oxide-YSZ (LSM-YSZ). In accordance with one embodiment of thepresent invention, porous cathode 202 is a ceramic oxide of perovskite.In at least one embodiment of the present invention, porous cathode 202does not include a liquid or an aqueous solution.

As shown in FIG. 3, carbon dioxide stream 45 mixes with steam supply 6to create fuel feed stream 4. Carbon dioxide stream 45 contains CO₂. Inat least one embodiment of the present invention, carbon dioxide stream45 also contains H₂O. Fuel feed stream 4 enters syngas production cell200 on fuel side 210 at fuel inlet 214. In an alternate embodiment ofthe present invention, fuel feed stream 4 and steam supply 6 enterssyngas production cell 200 through separate inlets. In at least oneembodiment of the present invention, prior to entering fuel inlet 214,fuel feed stream 4 is heated by transfer of heat from thermal energy 10(not shown) to create the heated fuel feed stream (not shown) at atemperature of between 500° C. and about 1000° C., alternately betweenabout 600° C. and about 900° C., alternately between about 650° C. andabout 800° C., and alternately between about 700° C. and about 800° C.Thermal energy 10 helps drive the electrochemical reaction.

In at least one embodiment of the present invention, the streams on fuelside 210 of syngas production cell 200 are in a gas phase, occurring inthe absence of a liquid or aqueous phase.

Fuel feed stream 4 contacts the fuel side of porous cathode 202 of SOEC220. On contact, porous cathode 202 provides electrons to the CO₂ andthe H₂O in fuel feed stream 4, which results in the co-electrolysis(reduction reactions) of CO₂ and H₂O.

The reduction reactions of CO₂ and H₂O proceed according to thefollowing chemistry:

2H₂O+4e ⁻->2H₂+2O²⁻  (reaction 1)

2CO₂+4e ⁻->2CO+2O²⁻  (reaction 2)

In reaction 1, hydrogen molecules and oxygen ions are produced at porouscathode 202. In reaction 2, carbon monoxide molecules and oxygen ionsare produced at porous cathode 202. The co-electrolysis of fuel feedstream 4 creates syngas stream 22, as described in reference to FIG. 1.

According to at least one embodiment, the oxygen ions created in thereduction reactions of CO₂ and H₂O move through porous cathode 202 tosolid oxide electrolyte 204. The oxygen ions then pass through solidoxide electrolyte 204 to porous anode 206. In accordance with at leastone embodiment of the present invention, solid oxide electrolyte 204includes yttria stabilized zirconia. In accordance with anotherembodiment of the present invention, solid oxide electrolyte 204includes cerium(IV) oxide (CeO₂) mixed with zirconia. In at least oneembodiment of the present invention solid oxide electrolyte 204 is inthe absence of a liquid or an aqueous phase.

Electron return 20 allows electrons to flow from porous anode 206, thusporous anode 206 is positively charged. The oxygen ions pass throughsolid oxide electrolyte 204 and then pass through porous anode 206. Theoxygen ions release electrons on oxygen side (not shown) of porous anode206 on oxygen side 208 of syngas production cell 200. In at least oneembodiment of the present invention, oxygen side 208 of syngasproduction cell 200 is in the absence of H₂ or H₂ evolution. The oxygenions on oxygen side of porous anode 206 undergo an oxidation reaction toform oxygen molecules, according to the following reaction:

2O²⁻->O₂+4e ⁻

Porous anode 206 includes, for example, any material which allows oxygenions to pass through from the electrolyte side (not shown) and acceptselectrons from oxygen ions to form oxygen molecules on the oxygen side(not shown). Porous anode 206 includes, for example, a cermet, acomposite material of ceramic and a metal. Cermets include, for example,nickel/yttria-stabilized zirconia (Ni-YSZ) or Lanthanum StrontiumManganese Oxide-YSZ (LSM-YSZ). In accordance with one embodiment of thepresent invention, porous anode 206 includes a ceramic oxide ofperovskite. In at least one embodiment of the present invention porousanode 206 is in the absence of a liquid or an aqueous phase.

The oxygen molecules, as oxygen stream 28, exit oxygen side 208 ofsyngas production cell 200 through oxygen outlet 228. In at least oneembodiment of the present invention, oxygen side 208 is in the absenceof a liquid or an aqueous phase. In accordance with at least oneembodiment, oxygen stream 28 is stored, fed to another processing unit,or transported to another location.

In at least one embodiment of the present invention, syngas productioncell 200, with SOEC 220 is a net consumer of electricity.

FIG. 4 provides a plan view of an embodiment of syngas production cell200, where syngas production cell 200 includes solid oxide fuel cell(SOFC) 230. SOFC 230 includes porous anode 206, solid oxide electrolyte204, and porous cathode 202, as described with reference to FIG. 3.

According to one embodiment of syngas production cell 200 as shown inFIG. 4, fuel feed stream 4 is a mix of carbon dioxide stream 45 andmethane stream 60. Methane stream 60 can be any source of a gaseoushydrocarbon. In at least one embodiment of the present invention,methane stream 60 contains gaseous hydrocarbons. In at least oneembodiment of the present invention, methane stream 60 includes anyhydrocarbons that are gaseous at the operating temperature of syngasproduction cell 200. In at least one embodiment of the presentinvention, methane stream 60 contains hydrocarbons that are gaseous atstandard temperature and pressure. In at least one embodiment of thepresent invention, methane stream 60 includes CH₄, C₂H₆, C₃H₈, andcombinations thereof. In at least one embodiment of the presentinvention, methane stream 60 includes CH₄.

In at least one embodiment of the present invention, fuel feed stream 4includes CO₂, H₂O, and CH₄. Fuel feed stream 4 enters syngas productioncell 200 on fuel side 210 at fuel inlet 214. In an alternate embodimentof the present invention, fuel feed stream 4 and methane stream 60 entersyngas production cell 200 through separate inlets. In at least oneembodiment of the present invention, steam is also fed to fuel side 210of syngas production cell 200 at anode 206. In at least one embodimentof the present invention, fuel feed stream 4 is in the gas phase,occurring in the absence of a liquid or aqueous phase.

At anode 206 the components, CO₂, CH₄, and H₂O of fuel feed stream 4undergo reforming reactions (steam reforming and dry reforming) andoxidation reactions to produce the syngas in syngas stream 22. In atleast one embodiment of the present invention, anode 206 acts as acatalyst for the reforming reactions. The reforming reactions proceedaccording to the following chemistry:

H₂O+CH₄→CO+3H₂

CO₂+CH₄→2CO+2H₂

The oxidation reactions proceed according to the following chemistry:

H₂+O²⁻→H₂O+2e ⁻

CH₄+O²⁻→CO+2H₂+2e ⁻

The oxygen ions of the oxidation reactions are produced at porouscathode 202 on oxygen side 208. Oxygen supply 24 is fed to oxygen side208 through oxygen inlet 218. Oxygen supply 24 can be any source ofoxygen. In at least one embodiment of the present invention, oxygensupply 24 is a pure source of oxygen (O₂). In an alternate embodiment ofthe present invention, oxygen supply 24 is air. In at least oneembodiment of the present invention, oxygen supply 24 is oxygen-enrichedair.

Electricity 18 supplies electrons to porous cathode 202, so porouscathode 202 is negatively charged. The O₂ in oxygen supply 24 contactsporous cathode 202 and oxygen ions (O²⁻) are generated. Excess oxygensupply 24 exits syngas production cell 200 through oxygen stream 28.

The oxygen ions diffuse through porous cathode 202 to solid oxideelectrolyte 204. The oxygen ions diffuse through solid oxide electrolyte204 to porous anode 206. The oxygen ions diffuse through porous anode206 to fuel side 210, where they react according to the oxidationreactions above.

The electrons released in the oxidation reactions pass through porousanode 206 and are carried by electron return 20 to electrical substation116. Electrical substation 116 combines electricity produced by solarthermal power system 100 (not shown) with electricity in electron return20 generated from syngas production cell 200. Electrical substation 116can be used to supply the local electric grid (not shown) or can be usedat other processing units (not shown).

In at least one embodiment of the present invention, syngas productioncell 200 with SOFC 230 is a net producer of electricity.

FIG. 5 is a schematic of an embodiment of carbon capture system 400.Carbon capture system 400 can be any carbon capture system capable ofisolating CO₂ and/or H₂O from flue gas stream 50. Carbon capture system400 includes, for example, any type of post-combustion, pre-combustion,or oxyfuel system. One conventional carbon capture system is describedas an example. One of skill in the art will appreciate that any carboncapture system must be adjusted to account for the composition of theflue gas and the desired composition of the fuel feed stream.

In accordance with one embodiment, flue gas 50 is fed from operatingunit 500 (not shown) as described with reference to FIG. 1. Flue gas 50is fed to the bottom of absorber 402 and flows up to the top of absorber402. Absorber 402 contains solvent from solvent stream 43 (i.e., a leansolvent stream, as discussed below) fed to the top of absorber 402. Thesolvent in absorber 402 includes, for example, an amine solvent, such aspotassium carbonate, or an organic amine. Absorber 402 includes, forexample, any type of absorption unit including a membrane absorber, apacked bed absorber, or a trayed column absorber. As solvent stream 43flows down through the absorber, the solvent in solvent stream 43contacts flue gas 50 flowing up through absorber 402. The CO₂ and atleast some of the H₂O vapor in flue gas 50 are absorbed into the solventcreating carbon dioxide rich solvent 41 which exits at the bottom ofabsorber 402. In accordance with one embodiment of the presentinvention, carbon dioxide rich solvent 41 is in the absence of H₂Ovapor. In accordance with at least one embodiment of the presentinvention, carbon dioxide rich solvent 41 includes all or substantiallyall of the H₂O vapor in flue gas 50. Waste gas 40, containingessentially no CO₂, exits the top of absorber 402 and can undergofurther processing and disposal steps as necessary for localenvironmental regulations, including, for example, scrubbingtechnologies and flare technologies.

As shown in FIG. 5, carbon dioxide rich solvent 41 is fed to heatexchanger 412. Heat exchanger 412 is, for example, a cross exchanger,where the heat from carbon dioxide lean solvent 47 is used to heatcarbon dioxide rich solvent 41.

Warmed carbon dioxide rich solvent 42 is fed to the top of regenerator404. Regenerator 404 can be any type of unit (e.g., a stripping unit)capable of handling the desorption of CO₂ from a solvent. Regenerator404 includes, for example, reboiler 414 which heats bottoms carbondioxide solvent 44 to a temperature between about 80° C. to about 120°C. The exact operating conditions depend on the type of solvent and thecomposition of CO₂ desired. Hot carbon dioxide solvent 46 entersregenerator 404 where the CO₂ separates from the solvent and exits ascarbon dioxide stream 45.

Carbon dioxide lean solvent 47 is fed to heat exchanger 412 where someof the heat from carbon dioxide lean solvent 47 is removed. Lean solvent48 is then fed to chiller 413 where the stream is cooled to below about40° C. Solvent stream 43 is then fed back to absorber 402.

Carbon dioxide stream 45 can be fed directly to syngas production cell200 or can be mixed with other stream to create fuel feed stream 4 asdescribed with reference to FIGS. 1, 3, and 4.

Although the present invention has been described in detail, it shouldbe understood that various changes, substitutions, and alterations canbe made hereupon without departing from the principle and scope of theinvention. Accordingly, the scope of the present invention should bedetermined by the following claims and their appropriate legalequivalents.

The singular forms “a,” “an,” and “the” include plural referents, unlessthe context clearly dictates otherwise.

Optional or optionally means that the subsequently described event orcircumstances can or may not occur. The description includes instanceswhere the event or circumstance occurs and instances where it does notoccur.

Ranges may be expressed herein as from about one particular value,and/or to about another particular value. When such a range isexpressed, it is to be understood that another embodiment is from theone particular value and/or to the other particular value, along withall combinations within said range.

Throughout this application, where patents or publications arereferenced, the disclosures of these references in their entireties areintended to be incorporated by reference into this application, in orderto more fully describe the state of the art to which the inventionpertains, except when these references contradict the statements madeherein.

As used herein and in the appended claims, the words “comprise,” “has,”and “include” and all grammatical variations thereof are each intendedto have an open, non-limiting meaning that does not exclude additionalelements or steps.

As used herein, terms such as “first” and “second” are arbitrarilyassigned and are merely intended to differentiate between two or morecomponents of an apparatus. It is to be understood that the words“first” and “second” serve no other purpose and are not part of the nameor description of the component, nor do they necessarily define arelative location or position of the component. Furthermore, it is to beunderstood that that the mere use of the term “first” and “second” doesnot require that there be any “third” component, although thatpossibility is contemplated under the scope of the present invention.

What is claimed is:
 1. A system to convert carbon dioxide to hydrocarbon fuels using solar energy, the system comprising: a solar thermal power system configured to convert solar energy to thermal energy and electricity, the solar thermal power system being in thermal communication with a syngas production cell, wherein the syngas production cell is configured to receive thermal energy from the solar thermal power system; the syngas production cell comprises a fuel side comprising a fuel inlet configured to receive a fuel feed stream and a fuel outlet configured to receive a syngas stream, and an oxygen side comprising an oxygen outlet configured to receive an oxygen stream, wherein the syngas production cell comprises a solid oxide electrolyzer cell, wherein the fuel feed stream comprises carbon dioxide and water, wherein the syngas production cell is configured to convert the carbon dioxide and water into carbon monoxide and hydrogen, the carbon monoxide and hydrogen operable to form the syngas stream; and a catalytic reactor fluidly connected to the fuel side of the syngas production cell, the catalytic reactor being configured to convert the syngas stream from the fuel side of the syngas production cell to a hydrocarbon fuel stream, the catalytic reactor comprising a reactor bed, the reactor bed comprising a catalyst and a distributor, wherein the catalytic reactor is configured to operate from 250° C. to 650° C.
 2. The system as claimed in claim 1, wherein the solid oxide electrolyzer cell comprises: a porous cathode in fluid communication with the fuel side of the syngas production cell, the porous cathode having a fuel side of the porous cathode configured to transfer electrons to the fuel feed stream, such that carbon monoxide, hydrogen, and oxygen ions are produced, and an electrolyte side configured to release the oxygen ions into a solid oxide electrolyte, wherein the porous cathode is configured to allow passage of oxygen ions; a porous anode in fluid communication with the oxygen side of the syngas production cell, the porous anode comprising an electrolyte side configured to receive oxygen ions from the solid oxide electrolyte, and an outlet side configured to convert oxygen ions to oxygen molecules to form an oxygen stream, wherein the porous anode is configured to allow passage of oxygen ions; the solid oxide electrolyte, the solid oxide electrolyte lies between the porous cathode and the porous anode, wherein the solid oxide electrolyte is configured to allow passage of oxygen ions; and an electron supply, wherein the electricity from the solar thermal power system provides the electron supply to the porous cathode and accepts electrons from the porous anode.
 3. The system as claimed in claim 2, wherein the porous cathode and the porous anode are selected from the group consisting of nickel/yttria-stabilized zirconia (Ni-YSZ), Lanthanum Strontium Manganese Oxide-YSZ (LSM-YSZ), and a ceramic oxide of perovskite.
 4. The system as claimed in claim 2, wherein the solid oxide electrolyte consists of yttria stabilized zirconia.
 5. The system as claimed in claim 1, wherein the solar thermal power system comprises a tower concentrating solar power system, the tower concentrating solar power system comprising: a tower receiver configured to heat a heat transfer fluid; a plurality of heliostats in proximity to the tower receiver, wherein the heliostats are configured to receive direct sunlight and reflect the direct sunlight from the heliostats as reflected sunlight onto the tower receiver; a hot storage tank fluidly connected to the tower receiver, the hot storage tank configured to store the heat transfer fluid; a steam generator fluidly connected to the hot storage tank, the steam generator configured to transfer heat from the heat transfer fluid to a water stream to create a generated steam stream; a steam turbine fluidly connected to the steam generator, wherein the generated steam stream is configured to drive the steam turbine; and an electric generator mechanically connected to the steam turbine, wherein the steam generator is configured to drive the electric generator to create electricity.
 6. The system as claimed in claim 1, wherein the syngas production cell is configured to operate from 650° C. to 800° C.
 7. The system as claimed in claim 1, further comprising a carbon capture system configured to capture carbon dioxide from a flue gas stream to create a carbon dioxide stream, the carbon capture system in fluid communication with a power plant, wherein the power plant is configured to produce the flue gas stream.
 8. A system to convert carbon dioxide to hydrocarbon fuels using solar energy, the system comprising: a solar thermal power system configured to convert solar energy to thermal energy and electricity, the solar thermal power system being in thermal communication with a syngas production cell, wherein the syngas production cell is configured to receive thermal energy from the solar thermal power system; the syngas production cell comprises a fuel side comprising a fuel inlet configured to receive a fuel feed stream and a fuel outlet configured to receive a syngas stream, and an oxygen side comprising an oxygen outlet configured to receive an oxygen stream, wherein the syngas production cell comprises a solid oxide fuel cell, and wherein the fuel feed stream further comprises a gaseous hydrocarbon, wherein the fuel feed stream comprises carbon dioxide and water, wherein the syngas production cell is configured to convert the carbon dioxide and water into carbon monoxide and hydrogen, the carbon monoxide and hydrogen operable to form the syngas stream; and a catalytic reactor fluidly connected to the fuel side of the syngas production cell, the catalytic reactor being configured to convert the syngas stream from the fuel side of the syngas production cell to a hydrocarbon fuel stream, the catalytic reactor comprising a reactor bed, the reactor bed comprising a catalyst and a distributor, wherein the catalytic reactor is configured to operate from 250° C. to 650° C.
 9. The system as claimed in claim 8, wherein the gaseous hydrocarbon comprises methane.
 10. The system as claimed in claim 9, wherein the solid oxide fuel cell comprises: a porous anode in fluid communication with the fuel side of the syngas production cell, the porous anode comprising a fuel side of the porous anode configured to accept electrons, such that the methane undergoes an oxidation reaction to form carbon monoxide, hydrogen, and electrons, and an electrolyte side configured to accept oxygen ions from a solid oxide electrolyte, wherein the porous anode is configured to allow passage of oxygen ions, wherein the methane and water react in the presence of the fuel side of the porous anode to generate carbon monoxide and hydrogen, and wherein the methane and carbon dioxide react in the presence of the fuel side of the porous anode to generate carbon monoxide and hydrogen; a porous cathode in fluid communication with the oxygen side of the syngas production cell, the porous cathode comprising an outlet side configured to convert oxygen into oxygen ions and an electrolyte side configured to release oxygen ions into the solid oxide electrolyte, wherein the porous cathode is configured to allow passage of oxygen ions; and the solid oxide electrolyte, the solid oxide electrolyte lies between the porous cathode and the porous anode, wherein the solid oxide electrolyte is configured to allow passage of oxygen ions.
 11. The system as claimed in claim 10, wherein the hydrogen in the fuel side of the syngas production cell undergoes an oxidation reaction to form water and electrons.
 12. The system as claimed in claim 10, wherein the porous cathode and the porous anode are selected from the group consisting of nickel/yttria-stabilized zirconia (Ni-YSZ), Lanthanum Strontium Manganese Oxide-YSZ (LSM-YSZ), and a ceramic oxide of perovskite.
 13. The system as claimed in claim 10, wherein the solid oxide electrolyte consists of yttria stabilized zirconia.
 14. The system as claimed in claim 8, wherein the solar thermal power system comprises a tower concentrating solar power system, the tower concentrating solar power system comprising: a tower receiver configured to heat a heat transfer fluid; a plurality of heliostats in proximity to the tower receiver, wherein the heliostats are configured to receive direct sunlight and reflect the direct sunlight from the heliostats as reflected sunlight onto the tower receiver; a hot storage tank fluidly connected to the tower receiver, the hot storage tank configured to store the heat transfer fluid; a steam generator fluidly connected to the hot storage tank, the steam generator configured to transfer heat from the heat transfer fluid to a water stream to create a generated steam stream; a steam turbine fluidly connected to the steam generator, wherein the generated steam stream is configured to drive the steam turbine; and an electric generator mechanically connected to the steam turbine, wherein the steam generator is configured to drive the electric generator to create electricity.
 15. The system as claimed in claim 8, wherein the syngas production cell is configured to operate from 650° C. to 800° C.
 16. The system as claimed in claim 8, further comprising a carbon capture system configured to capture carbon dioxide from a flue gas stream to create a carbon dioxide stream, the carbon capture system in fluid communication with a power plant, wherein the power plant is configured to produce the flue gas stream. 